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Re: Example Errors

From: Eric Prud'hommeaux <eric@w3.org>
Date: Mon, 18 Dec 2006 07:43:50 -0500
To: Ryan Levering <RRLevering@yahoo.com>
Cc: public-rdf-dawg@w3.org
Message-ID: <20061218124349.GL31800@w3.org>
On Fri, Sep 02, 2005 at 07:17:29PM -0400, Ryan Levering wrote:
> I never got around to giving more in-depth thoughts on the document.  Even
> though technically the deadline is passed for public comments, I thought I
> should at least mention that several examples in the value testing section
> are objectively incorrect, regardless of when comments are due :).

nope, sorry, we like our typos.

> The first example in for sop:RDFterm-equal should have two results
> in the query results section, with the inverse solution as well as the
> listed, since name1=>Ms A. and name2=>Alice is just as valid a binding.


> The second example in has a typo, the time in the data should be
> 19:00, not 19:01 like listed, to get the results expected.


> The first example in has several problems, so it's best to
> re-examine it.  Namely, the FILTER construct is missing a parenthesis (or
> should have the outside one removed) and the example appears to be
> projecting an undefined variable for no reason.


> The second example in should have foaf:givenName as the predicate,
> not foaf:name.


> The query under section 11 Testing Values should probably read "?date > ..."
> and not "?date < ...".  Otherwise, the same result will be returned in both
> examples, since neither of the dates in the data will test true, no matter
> whether the casting works or not.


> The example in should read "FILTER regex(?name...", not "FILTER
> regex(name..."


> This may actually present some issues in general, but example has a
> statement ""FILTER (lang(?name) = "ES" ) )"".  Technically, "ES" will parse
> to a untyped literal and the LANG function returns a xsd:string, which will
> by the constraints of the language result in a literal compare, which will
> fail in all cases.  To be technically accurate, it should read ""FILTER
> (lang(?name) = str("ES") ) )"".
> Section 10.2 has a typo in the query - "?name X" should have the space
> removed.
> In section 9.3, the default graph should actually be a named graph with the
> uri http://example.org/dft.ttl.
> In section 9.1, the default graph should actually be a named graph with the
> uri http://example.org/foaf/aliceFoaf.
> In section 8.4, the example is fairly confusing since the named graphs have
> different names than what they are called in the default graph.  This may be
> purposeful, as they might dynamically evaluate to the named graphs, but it's
> still a bit confusing.
> While I'm at it, I'll throw in a question: what's the difference between STR
> function and xsd:string cast constructor?  They seem redundant.
> Ryan Levering


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Received on Monday, 18 December 2006 12:44:09 UTC

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